Efficacy of talc-based formulation of Beauveria bassiana (Bals.) Vuill. (MZ749636) against two spotted spider mite, Tetranychus urticae Koch

Abstract

Tetranychus urticae is one of the most important and destructive mite species infesting the vegetable crops, which is very important to control because of its wide host range. The damage caused by the two spotted spider mite can be eliminated by using entomopathogenic fungi, as the acaricidal control causes various problems such as resistance, resurgence and residue problems. Therefore, the present study was carried out with a view to evaluate the efficacy of the talc-based formulation of Beauveria bassiana (MZ749636) under pot-culture conditions against two spotted spider mite (TSSM), T. urticae in potted bhendi (Abelmoschus esculentus) plants, in comparison with fenazaquin 10 EC @ 1.5ml/l, azadirachtin 3000 ppm @ 2ml/l and crude formulation of B. bassiana, MZ749636 @ 1 x 108 conidia/ml. After two rounds of spraying at fortnight intervals, the talc- formulation of B. bassiana, MZ749636 resulted in 62.83 per cent cumulative reduction of TSSM over the control. However, fenazaquin 10 EC @1.5 ml/l recorded the maximum cumulative mortality of 80.07 per cent, followed by azadirachtin 3000 ppm @ 2ml/l, which recorded a cumulative mortality per cent of 71.06 per cent. Crude formulation of B. bassiana recorded 58.12 per cent reduction of TSSM over the control after two rounds of spraying. This was the first study that attempted to evaluate the efficacy of the talc formulation of the B. bassiana (MZ749636) isolate against TSSM.